Microfluidic channels and chambers are interconnected to construct microfluidic devices (hereinafter referred to as “microfluidic chips”). Generally, microfluidic chips receive a sample (e.g., blood, bodily fluids) for reaction and/or detection within the device. For example, through a chemical interaction provided within the device, a signal is provided that is proportional to an analyte in the sample to be detected.
Reaction within the microfluidic chip is provided by mixing the sample with one or more reagents. Reagent storage on microfluidic devices is generally a cumbersome process. Assembly of the microfluidic devices is needed in humidity controlled environments. Additionally, the microfluidic devices need to be sealed in packaging that prevents, if not eliminates, light ingress. Even in use, unsealing a microfluidic device from a package is performed such that the device is not exposed to excessive humidity and light.
Foil pouches for reagent storage are used within the industry to protect against humidity, light, and the like. These pouches are opened by the application of a pressure in excess of the burst pressure such that the reagent may be released into the sample. For example, blister pouches are used within the industry to deliver reagents. See, for example, U.S. Pat. Nos. 6,159,747, 8,012,745, U.S. Pat. No. 8,105,849, 6,264,900, and U.S. Pat. No. 7,060,225. These pouches, however, are not designed for the use of dry reagents.
Dry reagents allow for a longer shelf life. In using dry reagents, however, applying pressure in excess of the burst pressure may not release the majority of the dry reagent from the pouch using current designs within the industry. This may interfere with the intended reaction between the sample fluid and reagent within the microfluidic chip.
Other methods within the industry for opening pouches (e.g., spikes, rollers, surface tension), also may not release the majority of the dry reagent from the pouch. See, for example, U.S. Pat. Nos. 4,965,047, 5,258,314, 7,060,225, and 6,916,113.